tor-android/external/badvpn_dns/dostest/dostest-server.c

568 lines
16 KiB
C

/**
* @file dostest-server.c
* @author Ambroz Bizjak <ambrop7@gmail.com>
*
* @section LICENSE
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the author nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <stdio.h>
#include <string.h>
#include <stdarg.h>
#include <stdlib.h>
#ifdef BADVPN_LINUX
#include <sys/types.h>
#include <sys/socket.h>
#endif
#include <misc/debug.h>
#include <misc/version.h>
#include <misc/offset.h>
#include <misc/open_standard_streams.h>
#include <misc/balloc.h>
#include <misc/loglevel.h>
#include <structure/LinkedList1.h>
#include <base/BLog.h>
#include <system/BAddr.h>
#include <system/BReactor.h>
#include <system/BNetwork.h>
#include <system/BConnection.h>
#include <system/BSignal.h>
#include "StreamBuffer.h"
#include <generated/blog_channel_dostest_server.h>
#define PROGRAM_NAME "dostest-server"
#ifdef BADVPN_LINUX
#ifndef SO_DOSDEF_PREPARE
#define SO_DOSDEF_PREPARE 48
#endif
#ifndef SO_DOSDEF_ACTIVATE
#define SO_DOSDEF_ACTIVATE 49
#endif
#endif
#define BUF_SIZE 1024
// client structure
struct client {
BConnection con;
BAddr addr;
StreamBuffer buf;
BTimer disconnect_timer;
LinkedList1Node clients_list_node;
};
// command-line options
static struct {
int help;
int version;
char *listen_addr;
int max_clients;
int disconnect_time;
int defense_prepare_clients;
int defense_activate_clients;
int loglevel;
int loglevels[BLOG_NUM_CHANNELS];
} options;
// listen address
static BAddr listen_addr;
// reactor
static BReactor ss;
// listener
static BListener listener;
// clients
static LinkedList1 clients_list;
static int num_clients;
// defense status
static int defense_prepare;
static int defense_activate;
static void print_help (const char *name);
static void print_version (void);
static int parse_arguments (int argc, char *argv[]);
static int process_arguments (void);
static void signal_handler (void *unused);
static void listener_handler (void *unused);
static void client_free (struct client *client);
static void client_logfunc (struct client *client);
static void client_log (struct client *client, int level, const char *fmt, ...);
static void client_disconnect_timer_handler (struct client *client);
static void client_connection_handler (struct client *client, int event);
static void update_defense (void);
int main (int argc, char **argv)
{
if (argc <= 0) {
return 1;
}
// open standard streams
open_standard_streams();
// parse command-line arguments
if (!parse_arguments(argc, argv)) {
fprintf(stderr, "Failed to parse arguments\n");
print_help(argv[0]);
goto fail0;
}
// handle --help and --version
if (options.help) {
print_version();
print_help(argv[0]);
return 0;
}
if (options.version) {
print_version();
return 0;
}
// init loger
BLog_InitStderr();
// configure logger channels
for (int i = 0; i < BLOG_NUM_CHANNELS; i++) {
if (options.loglevels[i] >= 0) {
BLog_SetChannelLoglevel(i, options.loglevels[i]);
}
else if (options.loglevel >= 0) {
BLog_SetChannelLoglevel(i, options.loglevel);
}
}
BLog(BLOG_NOTICE, "initializing "GLOBAL_PRODUCT_NAME" "PROGRAM_NAME" "GLOBAL_VERSION);
// initialize network
if (!BNetwork_GlobalInit()) {
BLog(BLOG_ERROR, "BNetwork_GlobalInit failed");
goto fail1;
}
// process arguments
if (!process_arguments()) {
BLog(BLOG_ERROR, "Failed to process arguments");
goto fail1;
}
// init time
BTime_Init();
// init reactor
if (!BReactor_Init(&ss)) {
BLog(BLOG_ERROR, "BReactor_Init failed");
goto fail1;
}
// setup signal handler
if (!BSignal_Init(&ss, signal_handler, NULL)) {
BLog(BLOG_ERROR, "BSignal_Init failed");
goto fail2;
}
// initialize listener
if (!BListener_Init(&listener, listen_addr, &ss, NULL, listener_handler)) {
BLog(BLOG_ERROR, "Listener_Init failed");
goto fail3;
}
// init clients list
LinkedList1_Init(&clients_list);
num_clients = 0;
// clear defense state
defense_prepare = 0;
defense_activate = 0;
// update defense
update_defense();
// enter event loop
BLog(BLOG_NOTICE, "entering event loop");
BReactor_Exec(&ss);
// free clients
while (!LinkedList1_IsEmpty(&clients_list)) {
struct client *client = UPPER_OBJECT(LinkedList1_GetFirst(&clients_list), struct client, clients_list_node);
client_free(client);
}
// free listener
BListener_Free(&listener);
fail3:
// free signal
BSignal_Finish();
fail2:
// free reactor
BReactor_Free(&ss);
fail1:
// free logger
BLog(BLOG_NOTICE, "exiting");
BLog_Free();
fail0:
// finish debug objects
DebugObjectGlobal_Finish();
return 1;
}
void print_help (const char *name)
{
printf(
"Usage:\n"
" %s\n"
" [--help]\n"
" [--version]\n"
" --listen-addr <addr>\n"
" --max-clients <number>\n"
" --disconnect-time <milliseconds>\n"
" [--defense-prepare-clients <number>]\n"
" [--defense-activate-clients <number>]\n"
" [--loglevel <0-5/none/error/warning/notice/info/debug>]\n"
" [--channel-loglevel <channel-name> <0-5/none/error/warning/notice/info/debug>] ...\n"
"Address format is a.b.c.d:port (IPv4) or [addr]:port (IPv6).\n",
name
);
}
void print_version (void)
{
printf(GLOBAL_PRODUCT_NAME" "PROGRAM_NAME" "GLOBAL_VERSION"\n"GLOBAL_COPYRIGHT_NOTICE"\n");
}
int parse_arguments (int argc, char *argv[])
{
options.help = 0;
options.version = 0;
options.listen_addr = NULL;
options.max_clients = -1;
options.disconnect_time = -1;
options.defense_prepare_clients = -1;
options.defense_activate_clients = -1;
options.loglevel = -1;
for (int i = 0; i < BLOG_NUM_CHANNELS; i++) {
options.loglevels[i] = -1;
}
int i;
for (i = 1; i < argc; i++) {
char *arg = argv[i];
if (!strcmp(arg, "--help")) {
options.help = 1;
}
else if (!strcmp(arg, "--version")) {
options.version = 1;
}
else if (!strcmp(arg, "--listen-addr")) {
if (1 >= argc - i) {
fprintf(stderr, "%s: requires an argument\n", arg);
return 0;
}
options.listen_addr = argv[i + 1];
i++;
}
else if (!strcmp(arg, "--max-clients")) {
if (1 >= argc - i) {
fprintf(stderr, "%s: requires an argument\n", arg);
return 0;
}
if ((options.max_clients = atoi(argv[i + 1])) <= 0) {
fprintf(stderr, "%s: wrong argument\n", arg);
return 0;
}
i++;
}
else if (!strcmp(arg, "--disconnect-time")) {
if (1 >= argc - i) {
fprintf(stderr, "%s: requires an argument\n", arg);
return 0;
}
if ((options.disconnect_time = atoi(argv[i + 1])) <= 0) {
fprintf(stderr, "%s: wrong argument\n", arg);
return 0;
}
i++;
}
else if (!strcmp(arg, "--defense-prepare-clients")) {
if (1 >= argc - i) {
fprintf(stderr, "%s: requires an argument\n", arg);
return 0;
}
if ((options.defense_prepare_clients = atoi(argv[i + 1])) <= 0) {
fprintf(stderr, "%s: wrong argument\n", arg);
return 0;
}
i++;
}
else if (!strcmp(arg, "--defense-activate-clients")) {
if (1 >= argc - i) {
fprintf(stderr, "%s: requires an argument\n", arg);
return 0;
}
if ((options.defense_activate_clients = atoi(argv[i + 1])) <= 0) {
fprintf(stderr, "%s: wrong argument\n", arg);
return 0;
}
i++;
}
else if (!strcmp(arg, "--loglevel")) {
if (1 >= argc - i) {
fprintf(stderr, "%s: requires an argument\n", arg);
return 0;
}
if ((options.loglevel = parse_loglevel(argv[i + 1])) < 0) {
fprintf(stderr, "%s: wrong argument\n", arg);
return 0;
}
i++;
}
else if (!strcmp(arg, "--channel-loglevel")) {
if (2 >= argc - i) {
fprintf(stderr, "%s: requires two arguments\n", arg);
return 0;
}
int channel = BLogGlobal_GetChannelByName(argv[i + 1]);
if (channel < 0) {
fprintf(stderr, "%s: wrong channel argument\n", arg);
return 0;
}
int loglevel = parse_loglevel(argv[i + 2]);
if (loglevel < 0) {
fprintf(stderr, "%s: wrong loglevel argument\n", arg);
return 0;
}
options.loglevels[channel] = loglevel;
i += 2;
}
else {
fprintf(stderr, "unknown option: %s\n", arg);
return 0;
}
}
if (options.help || options.version) {
return 1;
}
if (!options.listen_addr) {
fprintf(stderr, "--listen-addr missing\n");
return 0;
}
if (options.max_clients == -1) {
fprintf(stderr, "--max-clients missing\n");
return 0;
}
if (options.disconnect_time == -1) {
fprintf(stderr, "--disconnect-time missing\n");
return 0;
}
return 1;
}
int process_arguments (void)
{
// resolve listen address
if (!BAddr_Parse(&listen_addr, options.listen_addr, NULL, 0)) {
BLog(BLOG_ERROR, "listen addr: BAddr_Parse failed");
return 0;
}
return 1;
}
void signal_handler (void *unused)
{
BLog(BLOG_NOTICE, "termination requested");
// exit event loop
BReactor_Quit(&ss, 1);
}
void listener_handler (void *unused)
{
if (num_clients == options.max_clients) {
BLog(BLOG_ERROR, "maximum number of clients reached");
goto fail0;
}
// allocate structure
struct client *client = (struct client *)malloc(sizeof(*client));
if (!client) {
BLog(BLOG_ERROR, "malloc failed");
goto fail0;
}
// accept client
if (!BConnection_Init(&client->con, BConnection_source_listener(&listener, &client->addr), &ss, client, (BConnection_handler)client_connection_handler)) {
BLog(BLOG_ERROR, "BConnection_Init failed");
goto fail1;
}
// init connection interfaces
BConnection_RecvAsync_Init(&client->con);
BConnection_SendAsync_Init(&client->con);
StreamRecvInterface *recv_if = BConnection_RecvAsync_GetIf(&client->con);
StreamPassInterface *send_if = BConnection_SendAsync_GetIf(&client->con);
// init stream buffer (to loop received data back to the client)
if (!StreamBuffer_Init(&client->buf, BUF_SIZE, recv_if, send_if)) {
BLog(BLOG_ERROR, "StreamBuffer_Init failed");
goto fail2;
}
// init disconnect timer
BTimer_Init(&client->disconnect_timer, options.disconnect_time, (BTimer_handler)client_disconnect_timer_handler, client);
BReactor_SetTimer(&ss, &client->disconnect_timer);
// insert to clients list
LinkedList1_Append(&clients_list, &client->clients_list_node);
num_clients++;
client_log(client, BLOG_INFO, "connected");
BLog(BLOG_NOTICE, "%d clients", num_clients);
// update defense
update_defense();
return;
fail2:
BConnection_SendAsync_Free(&client->con);
BConnection_RecvAsync_Free(&client->con);
BConnection_Free(&client->con);
fail1:
free(client);
fail0:
return;
}
void client_free (struct client *client)
{
// remove from clients list
LinkedList1_Remove(&clients_list, &client->clients_list_node);
num_clients--;
// free disconnect timer
BReactor_RemoveTimer(&ss, &client->disconnect_timer);
// free stream buffer
StreamBuffer_Free(&client->buf);
// free connection interfaces
BConnection_SendAsync_Free(&client->con);
BConnection_RecvAsync_Free(&client->con);
// free connection
BConnection_Free(&client->con);
// free structure
free(client);
BLog(BLOG_NOTICE, "%d clients", num_clients);
// update defense
update_defense();
}
void client_logfunc (struct client *client)
{
char addr[BADDR_MAX_PRINT_LEN];
BAddr_Print(&client->addr, addr);
BLog_Append("client (%s): ", addr);
}
void client_log (struct client *client, int level, const char *fmt, ...)
{
va_list vl;
va_start(vl, fmt);
BLog_LogViaFuncVarArg((BLog_logfunc)client_logfunc, client, BLOG_CURRENT_CHANNEL, level, fmt, vl);
va_end(vl);
}
void client_disconnect_timer_handler (struct client *client)
{
client_log(client, BLOG_INFO, "timed out, disconnecting");
// free client
client_free(client);
}
void client_connection_handler (struct client *client, int event)
{
if (event == BCONNECTION_EVENT_RECVCLOSED) {
client_log(client, BLOG_INFO, "client closed");
} else {
client_log(client, BLOG_INFO, "client error");
}
// free client
client_free(client);
}
void update_defense (void)
{
#ifdef BADVPN_LINUX
if (options.defense_prepare_clients != -1) {
int val = num_clients >= options.defense_prepare_clients;
int res = setsockopt(listener.fd, SOL_SOCKET, SO_DOSDEF_PREPARE, &val, sizeof(val));
if (res < 0) {
BLog(BLOG_ERROR, "failed to %s defense preparation", (val ? "enable" : "disable"));
} else {
if (!defense_prepare && val) {
BLog(BLOG_NOTICE, "defense preparation enabled");
}
else if (defense_prepare && !val) {
BLog(BLOG_NOTICE, "defense preparation disabled");
}
}
defense_prepare = val;
}
if (options.defense_activate_clients != -1) {
int val = num_clients >= options.defense_activate_clients;
int res = setsockopt(listener.fd, SOL_SOCKET, SO_DOSDEF_ACTIVATE, &val, sizeof(val));
if (res < 0) {
BLog(BLOG_ERROR, "failed to %s defense activation", (val ? "enable" : "disable"));
} else {
if (!defense_activate && val) {
BLog(BLOG_NOTICE, "defense activation enabled");
}
else if (defense_activate && !val) {
BLog(BLOG_NOTICE, "defense activation disabled");
}
}
defense_activate = val;
}
#endif
}